Nannotax3 - ntax_cenozoic - Polycrater sp. two petals modified two absent Nannotax3 - ntax_cenozoic - Polycrater sp. two petals modified two absent

Polycrater sp. two petals modified two absent

Classification: ntax_cenozoic -> Coccolith families inc sed -> Alisphaeraceae -> Polycrater phase -> Polycrater sp. two petals modified two absent
Sister taxa: A. unicornis POL, A. gaudii POL, C. valliformis POL, P. sp. with lip-like borders, P. sp. minimum, P. sp. with slit, P. sp. ladle-like, P. sp. two petals modified two absent, P. sp.


Citation: Polycrater sp. two petals modified two absent Cros & Fortuno 2002
taxonomic rank: Species

Distinguishing features:
Parent taxon (Polycrater phase): Phase with quadrate, cup-like nannoliths
This taxon: Distal cup incomplete, two petals reduced to a rod-like structure, the other two absent

Farinacci & Howe catalog pages:


"The coccosphere has a spiny shape. The coccoliths have the sepal-like structure similar to the other Polycrater species, whilst the petal-like structure is completely modified: two petal-like elements are very reduced with the corner highly extended form- ing a stick of variable width; there are no more petal- like elements.
The species Ericiolus spiculiger Thomsen (Thomsen et al. 1995) appears morphologically related with this Polycrater sp., but the coccoliths of Ericiolus spiculiger do not show the  sepal-like proximal cross structures of Polycrater sp. coccoliths." [Cros & Fortuno 2002]

Coccosphere diameter 4-6 μm; coccolith length 0.4-0.7 μm, width in distal part variable (up to 0.3 μm)[Cros & Fortuno 2002]

Search data:
LITHS: nannolith-radiate, asymmetric, CA: ca_conjunct, closed,
CSPH: equant, monomorphic,
Lith size: 0->0µm;
The morphological data given here can be used on the advanced search page. See also these notes

Geological Range:
Last occurrence (top): Extant. Data source:
First occurrence (base): within No known fossil record modern (0-0Ma, base in "Holocene" stage). Data source:

Plot of occurrence data:


Cros, L. & Fortuño, J. -M. (2002). Atlas of northwestern Mediterranean coccolithophores. Scientia Marina. 66: 1-186. gs


Polycrater sp. two petals modified two absent compiled by Jeremy R. Young, Paul R. Bown, Jacqueline A. Lees viewed: 10-12-2023

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